std.concurrency : sending immutable classes

[Dejan Lekic]

Could it be something changed in DMD recently, as in my case (DMD64 D 
Compiler v2.063.2, on Fedora GNU/Linux) it obviously picks Variant. Why 
it does not pick the immutable instance of A is beyond me. If we reverse 
the order of arguments in the receive(), we will get the "function with 
arguments (VariantN!(32LU)) occludes successive function" error...